I’ve added a few more things to the Hebrew Dates plugin patches I mentioned earlier.

Latest changelog:

• Configuration screen shows when an update was performed
• Option of showing Hebrew (or transliterated) only, Gregorian – Hebrew, or Hebrew – Gregorian
• General code cleanup

Also, a known bug. The sunset routine cannot take into account GMT, since the wordpress offset is GMT +/-, not a timezone (not to mention the computational nightmare that is the Israeli timezone).